Systemic review: the pathogenesis and pharmacological treatment of hiccups.

BACKGROUND Hiccups are familiar to everyone, but remain poorly understood. Acute hiccups can often be terminated by physical manoeuvres. In contrast, persistent and intractable hiccups that continue for days or months are rare, but can be distressing and difficult to treat. AIM To review the management of hiccups, including a systematic review of reported efficacy and safety of pharmacological treatments. METHODS Available articles were identified using three electronic databases in addition to hand searching of published articles. Inclusion criteria were any reports of pharmaceutical therapy of 'hiccup(s)', 'hiccough(s)' or 'singultus' in English or German. RESULTS Treatment of 341 patients with persistent or intractable hiccups was reported in 15 published studies. Management was most effective when directed at the underlying condition. An empirical trial of anti-reflux therapy may be appropriate. If the underlying cause is not known or not treatable, then a range of pharmacological agents may provide benefit; however, systematic review revealed no adequately powered, well-designed trials of treatment. The use of baclofen and metoclopramide are supported by small randomised, placebo-controlled trials. Observational data suggest that gabapentin and chlorpromazine are also effective. Baclofen and gabapentin are less likely than standard neuroleptic agents to cause side effects during long-term therapy. CONCLUSIONS This systematic review revealed no high quality data on which to base treatment recommendations. Based on limited efficacy and safety data, baclofen and gabapentin may be considered as first line therapy for persistent and intractable hiccups, with metoclopramide and chlorpromazine in reserve.